Known in the art is an internal combustion engine in which an exhaust purification catalyst is arranged inside an engine exhaust passage and a hydrocarbon feed valve is arranged upstream of the exhaust purification catalyst in the engine exhaust passage, a precious metal catalyst is carried on an exhaust gas flow surface of the exhaust purification catalyst and a basic exhaust gas flow surface part is formed around the precious metal catalyst, the exhaust purification catalyst has the property of reducing the NOX which is contained in the exhaust gas when making the concentration of hydrocarbons which flow into the exhaust purification catalyst vibrate by within a predetermined range of amplitude and within a predetermined range of period and has the property of being increased in amount of storage of NOX which is contained in the exhaust gas if making the vibration period of the hydrocarbon concentration longer than the predetermined range, and NOX which is contained in the exhaust gas is removed by injecting hydrocarbons from the hydrocarbon feed valve by a predetermined period in a first NOX removal method (for example, see PLT 1). In this internal combustion engine, further, a particulate filter for trapping particulate matter in the exhaust gas is arranged downstream of the exhaust purification catalyst in the engine exhaust passage.
On the other hand, known in the art is also an internal combustion engine which raises the temperature of the particulate filter under a lean air-fuel ratio in temperature elevation control, in order to remove the particulate matter which has been trapped on a particulate filter by oxidation. In the internal combustion engine which is described in PLT 1, the air-fuel ratio of the exhaust gas which flows into the particulate filter can made to become lean by injecting hydrocarbons from the hydrocarbon feed valve in temperature elevation control.